Dimercaptide derivatives of distannoxanes or thiodistannoxanes



MITSUO ONOZUKA ET AL Dec. 15, 1970 3,547,961

NNOXANES OR THIODISTANNOXANES DI-MERCAPTIDE DERIVATIVES OF DISTA Filed April ll, 196

2 Sheets-Sheet l OQv Oom OO@ Oo @on Oom OO: OO@ OO@ ook OOON 00mm OOwm OO@ OOQN QOwm OOOW NOISSIWSNVHL LNBOHBd NOISSIINSNVHJ. LNSDHBd Dec. 1 5, 1970 Mrrsuo oNozUKA ETAL 3,547,961

DIMERCAPTIDE DERIVATIVES OF DISTANNOXANES OR THIODISTANNOXANES Filed April 1l, 1968 2 Sheets-Sheet 2 OOv 00m OO@ OO# OOON OOm 00mm OON 00m OQ OO@ OO@ OO OO@ OOvN 00mm OOOv OOON OON OOwm 00m. OOvN 00mm OOO@ O Ov Ow United States Patent O 3,547,961 DIMERCAPTIDE DERlVATIVES F DISTAN- NUXANES GR THIODISTANNOXANES Mitsuo Onozuka, Tokyo, Toshiaki Nakamura, Kashiwashi, and Kinji Iida, Tokyo, Japan, assignors to Kureha Kagaku Kogyo Kabushiki Kaisha, Tokyo, Japan, a corporation of Japan Filed Apr. 11, 1968, Ser. No. 720,724 Claims priority, application Japan, Apr. 13, 1967, 42/ 23,604 Int. Cl. C0715 7/22; C09f 5 08 U.S. Cl. 24W-410.6 7 Claims ABSTRACT 0F THE DISCLOSURE A high molecular solid state tin compounds especially adapted for use as thermal stabilizers for chloric or chlorine-containing artificial resins, and having the following general formula:

where, R1, R2, R3 and R4 stand for same or different organic radicals having one or more carbon atoms directly bonded to Sn; X and Y stand for the same or different (--S \CH2/u COO radicals, n Ibeing an integer l or 2; or more specifically same or dilerent mercapto-radicals of poly-mercapto-acid esters of polyols having sulfur atoms directly bonded to Sn. Z stands for oxygen or sulfur.

radicals, :z being an integer l or 2; or more specifically same or different mercapto-radicals of poly-mercapto-acid esters of polyols having sulfur atoms directly bonded to Sn. Z stands for oxygen or sulfur.

These compounds are dimercaptide derivatives of distannoxane or thiodistannoxane and may have a linear, ring, branched or cross-linked structure.

The high molecular solid state tin compounds according to this invention are highly suitable for use as stabilizers against extractive migration and have such superior characteristics to known non-poisonous octyl tin stabilizers. Among others, they have least poisoning effect to human bodies and a remarkable thermo-stabilizing performance. Since the said tin compounds give practically no smell inherent in mercapto-compounds which is a considerable drawback of sulfur-containing tin compounds, they are highly suitable for use as thermal stabilizers for foodstuff package material.

R1, R2, R3 and R4 appearing iu the above general formula may be alkyl (C1-C12), alkenyl (vinyl or allyl), aryl (phenyl radical and its derivatives), aralkyl (benzyl,

Patented Dec. l5, 1970 phenylethyl, tryl) cycloalkyl (cyclohexyl, 3-methyl cyclohexyl, 3-ch1orocyclohexyl and the like). X and Y stand for mercapto-radicals of mercapto-acid esters of same or different polyhydric alcohol. These may be mercapto-radicals of polythiols such as glycol di (thioglycolate), glycol di (3-mercaptopropionat'e), diethylene glycol di (thioglycolate), diethylene glycol di (3-rnercaptopropionate), glycerol tri (thioglycolate), glycerol tri (S-mercaptopropionate), pentaerythritol tetra (thioglycolate), pentaerythritol tetra (ES-mercaptopropionate), trimethylolethane tri (thioglycolate), trimethylolethane tri (I-mercaptopropionate), trimethylolpropane tri (thioglycolate), trimethylolpropane tri (3-mercaptopropionate), sorbitol hexa (thioglycolate), sorbitol hexa (3-mercaptopropionate), mannitol hexa (thioglycolate), mannitol hexa (Ii-mercaptopropionate) and the like. Compounds which have been prepared from polyols esterified partially by organic acids and partially by mercapto-acids.

Solid state tin stabilizers having the aforementioned general formula comprise a mercapto-radical of mercaptoacid ester and oxygen or sulfur bonded to each other per metallic tin atom, and rnercapto-acid ester in the form of an ester of polyhydric polyol represents its contained two or more tin atoms connected with each other or one after another, so as to represent a linear, ring, branched for cross-linked structure, thereby providing a kind of crosslinking agent.

When the solid state tin stabilizers compound is used with a chlorine-containing resin such as polyvinyl chloride, Several times of thermally stabilizing power as compared with that of the known organic tin dimercaptide stabilizer are obtained, as will be shown later more in detail hereinafter. The solid state tin compound stabilizer having a special structure, so to speak, is practically odorless and has such a remarkable nature that it will not separate out diflicult-volatile and ill-smelling substance even when subjected to a thermal inliuence as at a high temperature resin processing stage which nature is highly different from and superior to that of conventional liquid or solid state sulfur-containing tin stabilizer commercially available and hithertofore commonly utilized as working additive to foodstuff packaging material.

Nowadays commercially available non-poisonous tin stabilizer such as dioctyl tin-S,S-bisisooctyl mercaptoacetate has generally an acute toxicity (LD53) of about 4 g./kg., while that of the solid state tin stabilizer as obtained in Example 5 to be described amounts to l() g./ kg. or still higher which shows naturally a remarkable progress in the art. Other solid state tin compounds according to this invention (of dioctyl tin series) also show very low toxicity and have generally an acute toxicity (LD50) higher than about l0 g./kg.

A further advantage of the high molecule and solid state tin stabilizer according to this invention resides in a good mutual solubility with chlorine-containing resin, thus the stabilizer being capable of favorably and intimately mixing with the resin especially in the course of gelforming processing stage of the resin, in spite of a high melting point such as about C. of the stabilizer. An addition of plasticizer and/ or the like, acting as dispersant additive is not necessary, in this case, for thermal treatment' of that kind of resin. It is rather disadvantageous to employ an addition of conventional liquid dispersant additive for that purpose, Ibecause adverse effect upon the other properties of the resin under treatment could be nvited thereby. More specifically to say, when a small amount of conventional liquid state stabilizer is added to the resin for thermal processing of the latter, such considerable disadvantages as reduction of impact strength of the resin as well as reduction in utilizable temperature range for that purpose will generally be invited, which means naturally a conventional grave difficult problem which has not yet been solved out by those skilled in the art.

It has been found upon our profound practical experiments that an addition of the solid state tin stabilizer according to this invention to the resin in the course of thermal processing thereof that substantially no low temperature embrittlement of the resin and any considerable alteration of secondary transition temperature thereof will not be invited thereby, which means a creation of remarkable additive usable in the course of resin processing at elevated temperatures.

The high molecular solid state tin stabilizer according to this invention may be added in quantities between 0.1- parts by weight to the resin to be thermally treated based upon 100 wt. parts thereof, which resin may preerably be polyvinyl chloride; copolymer of the latter with other vinyl monomer, comprising 60 mol percent or higher percentage of polyvinyl chloride, a composition of said polymer and copolymer; a resin mixture comprising said both and further containing an amount of modifier, such as impact strength improving agent or the like, excepting halogen-containing resins.

The Weather fastness performance of the stabilizer according to this invention is highly superior to that of conventional liquid state, sulfur-containing stabilizers, although, as commonly known to those skilled in the art, sulfur-containing tin stabilizers are highly defective in this respect. This improved performance constitutes therefore and among others a remarkable feature of the stabilizer according to this invention, which performance can naturally `be improved still further by addition of conventional ultraviolet absorbing agent, plasticizer or the like. Selective addition of other processing additives such as lubricant, plasticizer, stabilizer and/ or the like may be made in accordance with the desired final properties of the resin to be treated and the processing conditions for the latter, `as will be easily thought out commonly by those skilled in the art.

In the following, a preferred process for the manufacture of the high molecular solid state tin stabilizer according to this invention will only briefly be described, which must be construed however to be in no limiting sense of the invention.

The new compounds according to this invention and highly suitable for use as the stabilizer in the aforementioned sense can be prepared by the reaction of the mercapto-radical of a polythiol with an equivalent amount of an organic tin oxide in the form of or an organic tin sulfide in the form of R-n-R in the presence of an inert solvent such as n-heptane, kerosine, benzene, toluene and/or the like at an elevated temperature under refluxing conditions for several hours so as to subject the reagents to a dehydration and then the solvent is distilled off. In place of said tin oxide, organic tin hydroxide, organic tin alkoxide, or derivatives of tetra-alkyl-l, 3-distannoxane or thiodistannoxane of the following either formula may be used for the synthetic Or alternatively, said oragnc tin oxide and polythiol may be mixed thoroughly together at room temperature or under slightly elevated temperatures for providing the desired product in an easy way, yet with a high yield.

In an alternative way, organic tin oxide and polythiol may be blended separately with chlorine-containing resin under dried conditions and the thus blended separate resin masses are kneaded together on a pair of mixing rolls with the roll peripheral surfaces kept at properly elevated temperatures such as 1Z0-160 C. In the course of this kneading process, the desired organic tin stabilizer is being synthetically formed. It was surprisingly found that the thermal stability of the thus stabilized resin bears cornparison with that of the corresponding resin which has been stabilized in the aforementioned manner wherein the resin has been stabilized separately by mixing previously it with the same thermal stabilizer, yet synthesized beforehand.

It is further possible to prepare a reaction compound which has the same composition as that of the organic tin compound according to the invention by providing the known dialkyl-tin-(S,Sbis-mercapto-acid-ester) compound with an equimolar dialkyl tin oxide. The thus prepared compound comprises a framework of the distannoxane and has therefore a highly improved thermal stabilizing performance.

It has been further found that for the thermal stabilization of halogencontaining resin, said organic tin oxide and organic sulfur compound having HS-radical may be simultaneously used, thereby providing a potentiatingly improved thermal stability.

`In spite of the fact that when the organic tin oxide and the organic sulfur compound are applied individually to the halogen-containing resin, the thermally stabilizing effeet thereby attained is only slight, the effect is very remarkable and potentiatingly improved when the substances are used simultaneously. This remarkable effect will not be lost in any way even when the organic tin oxide and the organic sulfur compound are used in combination with anhydrous dibasic acid such anhydrous maleic anhydride. The desired effect will not be obtained when an organic tin chloride such as dibutyl tin chloride in place of the organic tin oxide is used in combination with the organic sulfur compound such as thioglycolic acid.

The remarkable and potentiatingly improved effect obtainable in accordance with the novel teaching proposed by the invention may be maintained with the mol ratio of the organic tin oxide to the organic sulfur compound being selected to a value ranging from 1:0.1 to 1:20, most advantageous 1:1. The reason for this is naturally attributable -to the fact that the related two components are brought into reaction with each other to `the compound according to this invention.

When the organic tin oxide is used in an excessive amount from the usuable range specified above, an orange yellow color tone will be brought about. When the organic tin oxide is used in its smaller quantity relative to the organic sulfur compound than the recommendable range as above specified, an initial yellow brown coloring effect will be invited to take place which is naturally defective. But, when the amount of usage is kept within the above specified range, a highly eicient thermal stabilizing effect will be assured and substantially no disadvantageous coloring effect will be encountered, even at considerably elevated temperatures.

EXAMPLE 1 24.9 g. of dibutyl tin oxide and 11.9 g. of glycol di (3- mercaptopropionate) were added to ml. of benzene and heated under refluxed conditions for 2 hours for subjecting the reagents to a dehydrating reaction. The reaction proceeded at lirst in a heterogeneous system, but, with progress of the reaction, reaction products were separated out in the benzene phase in a dispersed state. Upon the separating formation of water in a stoichiometrio quantity, benzene and water were distilled off under rea duced pressure (110 mm. Hg), a viscous high molecular tin stabilizer 0f the following structure was obtained. Yield: 98%. M.P.: room temperature to 70 C. index of refraction HD2 1.5592. Specific gravity: 1.42. Upon measurement of weight decrease inclination on a diiierential thermo-balance, no appreciable weight variation was observed until 250 C.

EXAMPLE 2 24.9 g. of dibutyl tin oxide and 12.8 g. of trimethylol ethane tri(3-mercaptopropionate) were added to 100 ml. of benzene and heated under reiiuxed condition for 2 hours. The reaction proceeded at first in a heterogeneous emulsion system, but, with progress of the reaction, the viscosity of the system increased gradually. Upon the Wa-ter thus formed being separated out, benzene and water were distilled off under reduced pressure (10 mm. Hg) and a solid state high molecular tin stabilizer having the following branched or cross-linked structure was obtained with a yield of 99%. M.P.: 11G-155 C.; 11,320 1.5548; specific gravity: 1.35. Upon measurement of weight reduction inclination on a diiferential thermo-balance, no appreciable weight variation was observed until 250 C. Any decomposition product or formation of easily volatile substance was not observed.

CH CH 4949 CHC CH CH CH3 49.49 CHCH tar and mixed thoroughly together at room temperature. At iirst, the reaction mixture took the shape of a gelled mass, and, with progress of the reaction, it became a paste which was gradually solidified. Upon kneaded thoroughly for about 10 minutes, the solidified mass was kneaded in a mill to a line powder. When this powder mass was preserved for a considerably long time, it solidies itself into a solid block.

The high molecular solid state tin compound thus prepared showed a similar ultra-red absorption spectrum, as shown in FIG. 1, to that of the product obtained in Example 3. As seen from FIG. 1, the absorption (2560 cm.1) of SH radical of the starting material polythiol has been disappeared. The thermal stabilizing performance of the organic tin compound prepared in this example is shown in Example 29 to be described.

EXAMPLE 5 76.2 g. of dioctyl tin oxide and 25.8 g. iof pentaerythritol tetra (S-mercaptopropionate) were added to 100 ml. of toluene and heated under refluxed conditions for 3 hours. Upon removal of a stoichiometric quantity of formed water, the solvent was removed in vacuo (100 mm. Hg). A solid state high molecular tin compound, the molecular weight being 2173, was obtained with a reaction yield higher than 99%. M.P.: 154-157 C.; specific gravity: 1.21; nDz" 1.5308. Upon measurement of weight decrease inclination on a differential thermolbalance, the weight Variation was observed at 225 C. to begin. The ultra-red absorption spectrum is shown in FIG. 2 wherein the characteristic zones of distannoxane (5 65 cmr; near 600 cml) are observed.

It is well supposed that the products are mainly occupied by the following compound and added with a small quantity of its dimer.

42.7 g. of stearic acid, 20.4 g. of pentaerythritol and 2 g. of ptoluene sulfonic acid were added to 100 ml. of solvent toluene. The reaction mixture was heated under refluxed conditions for 2 hours to initiate and maintain an esterizing reaction, and then 47.7 g. of 3-mercapto propionic acid for further continuing the esterizing reaction. Upon acknowledgement of distilling ol of substantially stoichiometric quantity of formed water out f the reaction system, the solvent was removed in vacuo (100 mrn. Hg).

38.7 g. of the thus prepared monostearyl pentaerythritol tri(3-mercaptopropionate) and 62.9 g. of dioctyl tin oxide were charged into a ceramic mortar, 500 ml. capacity, (OBHH)2SH S CH2CH2C00GHz CHZOOCCHHM and mlxed thoroughly together at room temperature. After l lapse of several minutes of the mixing operation, the (l) paste-like mixture solidified gradually and became diicult (CiHnhSu-S-CHiCHzCO 00H2 CHZO OCCnHss te agitate After solidified, the mees was finely divided by with a reaction yield higher than 99.0%. M.P. 35-85 C.; rneans of a pestle into a powder which was then placed spccic gravity; 1 07; D20 15030; thermal decomposi 1n a constant temperature chamber kept at 60 C. and l, tion point 220e C E) dried therein for 2 hours 1n vacuo. 100 mm. Hg. If necesy EXAMPLE 9 sary, the drying step may be omltted without disadvanl tageously affecting the thermo-stabilizing effect. In the 30.3 g. of d1butyl tin drchloride and 12.2 g. of pentaabove-mentioned Way, the following solid state high molecelythfltol tetra(3me1`CaPt0P1 OPIOnae) Were ldded t0 100 ular tin compound was obtained with a reaction yield m1- Of toluene and heated 1n the presence 0f acid sodium higher than 99%, M.P.; 35 83 C Specic gravity; 1,11; carbonate (8.4 g.) for 3 hours. In order to complete the 111320: 1.5140; thermal decomposition point 225 C. An reactlon, 12 g. of.Na2S.9H2O are added to the reaction ultra-red absorption spectrum of this compound is shown mixture, and a solld state high molecular tin stabilizer of in FIG, 3, The compound was determined to be Same the following structure was obtained with a reaction yield as that obtained in Example 5, 5 of 98%. M.P. 1Z0-160 C.; nDZU 1.5692; specic gravity 05H17 04H0 /C4H9 \Sn-SCH2CH2COOCH2 CHQOOCCUHM SII-S-OHZCHzCOOCHz CHzOOCCHzCHiS-Sn I 03H17 (34H9 04H9 o s CQ l C l l /C4H9 /sn-SCHQCHZCOOCHZ CH2ooCCH2CHis-sr1\ Sn-s-Crncmooocnz CHzooccHzCHQs-sg CsHu 03H11 CsHu-IZ 04H 04H9 (|34H9 04H0 04H9 04H9 -S-sn-s-sn-s-CHZCHZC00GHz CHZOOCCHZGHzs-sn-s-sn-s- 04H0 iHv ClHu 04H CqHp C4139 04H9 04H1; S-n-S-n-S-CHZCHZCOOCHZ CHzOOCCHzCHzS-SIn-S--n-S- 04H0 04H 04H9 04H9 EXAMPLE 7 EXAMPLE 10 76,7 g of dioctyl tin Oxide and 253 g of ethy1ene 138 g. of l,1,3,3-tetrabutyl-1,3-dichloro-1,3-distannoxglycol di(3mercaptopropionate) were added to 100 ml. ane 112-1 14 C), 73 g- 0f monolanryl Pellfaeof toluene and heated under reuxed conditions for 3 50 Tlfthfltoltf1(3'Ine1'CaPt0P1'0P10nate) and 25 g- Of aCld S0- hours for carrying out a dehydrating reaction. Upon rednln'l Carbonate Were added .t0 300 m1 0f tehlene and moval of substantially a stoichiometric amount of the heated undef Tenx'lng Condltlons fOI' 3 POUI'S, 111 Order t0 formed Water, the solvent and Water were completely complete the react1on of the demlnerallzation. After the removed. In this Way, a paste-like compound was obtained reaction; removing ne Separated I n'eCiPlte and then with a reaction yield higher than 99%; molecular weight: 55 Condenslng the Spinnen, the OHOYVlng S011d State C0111- 855; M.P.: room temperature-70 C.; specific gravity: Pound Was Obtained Wlth d Yeeelon Yield higher than 1.19; nD20: 1.5248; Ithermal decomposition point 225 C. 98%- M-P- 50-90 C-i SPeClne gfaV1Y1-30S "D20 1-5372- An ultra-red absorption spectrum is shown in FIG. 4 CH from which the following structure may be given:

S11"S-CH2C:H2COO CH2 CH2-OOCC11II23 (CsHx7)2S|!1S- CHz-CHz-C O O-CHz 04H9 i l (CsHi7)zSn-S-OHz-CHa-COO-CH2 Srl--S-CHZCHQCOOCHZ CHgOOCCHzCHzS-n O 04H 04H9 l2 EXAMPLE 8 EXAMPLE 11 16.1 g. of pentaerythritol, 67.3 g. of stearic acid and 2 g. of p-toluene sulfonic acid were added to 100 m1. 138 g- 0f 1,1,3,3-etfab11ty1-1,3-deh10f0-1,3-dSaI1I10X- of benzene and heated under reuxed conditions for 2 ane, 85 g. of dilauryl pentaerythritol di(3rnercaptopro hours to carry out partial esterication. Next, 25.1 g. of pionate) and 25 g. of acid sodium carbonate were added 3-mercaptopropionic acid were added to the reaction mixture so as to complete the esterication. Upon distillating removal of substantially a s-toichiometric amount of the formed water from the reaction system, the solvent and water were completely distilled off.

to 300 ml. of toluene and heated under refluxing conditions for 3 hours in order to complete the reaction of the demineralization. After the reaction, removing the separated precipitate and then condensing the solution, the following solid state compound was obtained with a re- Srl-SCHgCHzCOOCg CHzOOC-CHHQ;

EXAMPLE 12 53.9 g. dibutyl tin oxide and 48.1 g. of monostearyl ipentaerythritol tri( 3-mercaptopropionate) were charged into a ceramic mortar, 500 ml. capacity, and mixed thoroughly together at room temperature. After lapse of several minutes of the mixing operation, the mixture became paste-like and solidified gradually with the progress of reaction. After solidified, the mass was nely divided by means of a pestle into a powder which was then placed in a constant temperature chamber kept at 60 C., dehydrated and dried for 2 hours. In the above-mentioned way a solid state tin compound was obtained with a reaction yield higher than 98%. M.P. 55-115 C.; specific gravity: 1.29; 111320 1.5325.

EXAMPLE 13 37.6 g. of dibutyl tin oxide and 63.8 g. of distearyl pentaerythritol di(3mercaptopropionate) charged into a ceramic mortar, 500 ml. capacity, and mixed thoroughly together at room temperature. After lapse of several minutes of the mixing operation, the mixture became pastelike and solidified gradually with the progress of the reaction. After solidified, the mass was finely divided by means of a pestle into a powder which was then placed in a constant temperature chamber kept at 60 C. dehydrated and dried for 2 hours. In the above-mentioned way a solid state tin compound was obtained with a reaction yield higher than 97%. M.P. room temperature--ll0 C.; specific gravity:1.04; nD20 1.5182.

c4ir9 sn-sca2cu2coocrr2 cazooo cunas crrg 10 EXAMPLE 14 117 g. of 3-mercaptopropionic acid, 31 g. of sorbitol and 4 g. of p-toluene sulfonic acid were added to 300 ml. of solvent toluene and esterified under reliuxing conditions for 4 hours. Upon removal by distillation of a stoichiometric quantity of the formed water, the solvent and water were completely distilled off under reduced pressure mm. Hg).

249 g. of dibutyl tin oxide and g. of the thus prepared sorbitan hexa (3-mercaptopropionate) charged into a ceramic mortar, capacity 500 ml., .mixed and kneaded thoroughly together. After lapse of about ten minutes of the mixing and kneading operation, the mass was finely divided into a powder by means of a pestle. In this way, the following solid state tin compound was obtained with a reaction yield higher than 98%. M.P. 96-135 C.; specifc gravity: 1.38 HD2() 1.5572.

EXAMPLE 15 100 g. of thioglycol, 31 g. of mannitol and 4 g. of ptoluene sulfonic acid were added to 300 ml. of solvent toluene and esteriiied under reliuxing conditions for 4 hours. Upon removal by distillation of a stoichiometric quantity of the formed water, thel solvent and Water were completely distilled olf under reduced pressure (100 mm. Hg).

249 g. of dibutyl tin oxide and 116 g. of the thus prepared mannitol hexa(thioglycolate) charged into a ceramic mortar, capacity 500 ml., mixed and kneaded thoroughly together. After lapse of about 10 minutes of the mixing and kneading operation, the mass was inely divided into a powder by means of a pestle'. In this way, a solid state tin compound was obtained with a reaction yield higher than 97 M.P. 110-155 C.; specific gravity: 1.34; HD2 1.5497.

SI1-S0112@ OO-CH (34H9 l 1 EXAMPLE 16 50 g. of lauric acid, 34 g. of pentaerythritol and 4 g. of p-toluene sulfonic acid were added to 300 ml. of solvent toluene, and heated under retluxing conditions for 2 hours. In order to lcontinue the esterifying reaction, 69 g. of thioglycolic acid were added. Upon removal by distillation of substantially stoichiometric amount of the formed water from the reaction system, the solvent was completely distilled off in vacuo (100 mm. Hg).

88 g. of the thus prepared monolauryl pentaerythritol tri(thiog1ycolate) and 125 g. of dibutyl tin oxide were charged into a ceramic mortar, capacity being 500 ml. and mixed thoroughly together. Upon lapse of several minutes of the mixing procedure, the reaction mixture solidified through its paste-like intermediate state. The thus solidified mass was finely divided by means of a pestle and the powder was introduced into a constant temperature chamber kept at 60 C. and dried for 2 hours for dehydration. In this way, a solid state high molecular tin compound was obtained with a reaction yield higher than 98%. M`-P. 50- 110 C.; specic gravity: 1.31; HD2() 1.5392.

EXAMPLE 17 100 g. of lauric acid, 34 g. of pentaerythritol and 4 g. of p-toluene sulfonic acid were added to 300 ml. of solvent sn-scHZcoocH2 n 23 Cul'lzaCOOCl-lg CHZOOC CMH23 EXAMPLE 18 13 g. of malonic acid, 34 g, of pentaerythritol and 2 g. of p-toluene sulfonic acid were mixed together and subjected for two hours under retluxing conditions to esterification. Then, 87.5 g. of 3-mercaptopropionic acid were added to the reaction mixture for continuing the esterilication. Upon removal by distillation of a stoichiometric amount of the formed Water from the reaction system, the solvent was completely driven off in vacuo (100 mm. Hg).

14.5 g. of the thus formed dipentaerythritol malonate ramic mortar capacity being 500 ml. and mixed thoroughramic mortar, capacity being 500 ml. and mived thoroughly together at 80 C. for about 30 minutes. Upon elapse of several minutes, the mass took a paste-like state which was then gradually solidified with progress of the reaction and finally turned into a solid. This solid mass was finely divided by means of a pestle and the powder was placed in a constant temperature chamber kept at C. for 2 hours for careful drying and dehydration. Thus, a solid state high molecular tin compound of the following structure was obtained with a reaction yield higher than 98%. M.P. -180 C.; specific gravity: 1.36; nD20 1.5477. In the following formula, nl:

toluene and subjected under reuxing conditions for 2 hours for carrying out the e'sterification. In order to further continuing the esterification, 46 g. of thioglycol were adde'd to the reaction mixture. Upon removal by distillation of substantially stoichiometric quantity of the formed water from the reaction system, the solvent was complete- 1y distilled off in vacuo (100 mm. Hg).

g. of the thus formed di-lauryl pentaerythritol di- (thioglycolate) and 125 g. of dibutyl tin oxide were charged into a ceramic mortar, capacity being 500 ml., and mixed thoroughly together at room tempearture. The mixture became within several minutes a paste, harder and harder with progress of the reaction and finally a solid mass, which was finely divided by means of a pestle and dried in a constant temperature chamber kept at 60 C. for 2 hours for careful dehydration, to provide a solid state high molecular tin compound. Reaction yield: higher than 96%. M.P. room temperature-110 C.; specific gravity: 1.17; HD2 1.5168.

EXAMPLE 19 g. of dioctyl tin oxide and 54 g. of pentaerythritol tetra (thioglycolate) were added to 300 ml. of solvent toluene and heated under reuxing conditions for 3 hours. Upon removal by distillation of a stoichiometric quantity of the formed water, the solvent was completely distilled oi in vacuo (100 mm- Hg) and a compound of the following structure was obtained with a reaction yield higher than 98%. Molecular weight: 1988; M.P. 146-150 C.; specific gravity: 1.21; 111320 1.5302.

36.1 g. of dioctyl tin oxide and 12.8 g. of trimethylol ethane tri (3-mercaptopropionate) were added to 100` ml. of solvent toluene and heated under reluxing conditions for 3 hours for carrying out dehydration. Upon removal by distillation of a stoichiometric quantity of the formed water, the solvent and water were completely distilled ofI. In this way, solid state high-molecular tin compound was obtained with a reaction yield higher than 96%. M.P. 90- 140" C.; specific gravity: 1.18; 711320 1.5288.

(cBH)sr-SCHzcHzcoocH2 cH3 o c (c H sii-SCH cH coocH/ \cH ooccH cH s-sn o s 172 2 2 2 2 .z 2 I z (C H l a 7 C H17 UaHw l 2 s( .s- -sn-scHZcHzcoocH2 CH3..4 i

CH17 C8H17 c H c H 17 s 17 C11H17 C51117 Ws n-oQsn-scn cH cooc cH ooccH CH s-sn- 2 2 2 2 2 An, CsHn CsHH C11H17 C11H17 EXAMPLE 22 36.1 g. of dioctyl tin oxide and 11.4 g. of trimethylol ethane tri(thioglycolate) were added to 100 ml. of toluene and heated under refluxing conditions for 3 hours for dehydration. Upon removal by distillation of a stoichiometric quantity of the formed water from the reaction system, the solvent and water were completely driven of in vacuo, a solid state high molecular tin compound was obtained with a. reaction yield higher than 98%. M.P. 87-136 C.; specific gravity: 1.22; 711320 1.53.17.

23.4 g. of pentaerythritol and 34.4 g. of lauric acid were added to 300 m1. of solvent benzene with 4 g. of p-toluene sulfonic acid and the mixture was heated under reuxing conditions for 2 hours to subject it to partial esterification. In order to complete the esterication, 54.6 g. of 3- mercaptopropionic acid were added. Upon removal by distillation of substantially a stoichiometric quantity of the formed water, the solvent and water were completely driven oi in vacuo.

35.6 g. of the thus formed monolauryl pentaerythritol t1i(3mercaptopropionate) and 66.2 g. of dioctyl tin oxide were charged into a ceramic mortar, capacity being 500 ml., and thoroughly mixed together at room temperature.

Upon elapse of several minutes of the mixing procedure the original viscous slurry-like mixture became gradually still further viscous and solidiied through the paste-like state into a solid mass. The reaction yield amounted higher than 98%. M.P. 48-86 C.; specific gravity: 1.12; m32 1.5179. The structure of the thus obtained new compound is:

20.1 g. of pentaerythritol, 59.2 g. of lauric acid and 4 g. of p-toluene sulfonic acid were added to 300 ml. of solvent benzene and the mixture was heated under reuxing conditions for 2 hours for partial esterication. For completing the esterication, 31.4 g. of 3-mercaptopropionic acid were added to the reaction mixture. Upon removal by distillation of the formed water from the reaction system, the solvent and water were completely driven olf in vacuo. 49.0 g. of the thus formed dilauryl pentaerythritol di (3-mercaptopropionate) and 52.4 g. of dioctyl tin oxide were charged into a ceramic mortar, capacity being 500 m1., and mixed thoroughly together at room temperature. Upon elapse of several minutes of the mixing procedure, the paste-like mixture became gradually more viscous and finally solidied into a solid mass. In this way, a solid state high molecular tin compound was obtained with a reaction yield higher than 99%. M.P. room temperature-67 C.; specific gravity: 1.08; 713320 1.5090.

coocH2 cHZooccuH23 8 17.

Comparative test 1 01H9 S-CHiCHi-Coo-CHZ /Sn\ 04H9 s-oHzom-Coo-CHZ n where, n is an integer 1 or 2.

1 5 EXAMPLE 26 Comparative test 2 in vacuo and then a solid state high molecular tin coml pound of the following structure was obtained with a yield of 95%.

/CH3 Sn C 180 C. for carrying out each case a long period test on static thermal stability. As may be well judged from the results listed in the table, the solid state high molecular tin compounds (refer to Al-A4) according to this invention represent highly superior performance in long period thermal stability to those of conventional comparative sulfur-containing tin compounds (refer to comparative Al-A4).

The rolled sheet was cut into small pieces (sizes: such as 5 cm. X 5 cm.). Three sheets of these cut pieces were stacked one after another and placed between two chromium-plated, l mm.thick steel sheets. The assembly thus prepared was then put on a testing press machine and CIg\S-CH2-CH2COOC2 \CHzOOC-CH2'CH2S\ /Cd-IQ 2o sn C@ S-CI-n-CH2-COOCI\I2 CHzOOC-CHz-CHZS 04H9 /S /C\ 03H9 SCHZ-CH2COOCH2 CH3 n Where n 1S anmteger 1 or 2' pressurized with 50 kgs/cm.2 at 190 for 10 minutes. EXAMPLE 27 Then, the assembly was taken out from the machine Comparative test 3 30 and subjected to blending and observed by naked eyes 243 g. of dibutyl tin dichloride and 196 g. of pentae'- rithritol tetra(S-mercaptopropionate) were added to 500 ml. of solvent benzene and heated in the presence of acid for possible whitening. It was ascertained that all of the test samples (A1-A4) conditioned by the stabilizers according to this invention showed practically no Whitenlng.

TABLE I Resin, pilhylgi Degree of decoloration upon heated at 180 C.

l uhder pressure for several minutes: Remarks, Nomination of (p 800) mercaptan samples (parts) Stabilizer (parts) 0 15 30 45 60 smell (100) Example 1 (1) Colorless.. colorless.- Colorless.. Colorless.- Yellowish..- None. (100) Example 2(1)... -do do do do do Do.

(100) Example 3 (1)..- do .do do-.- Do.

(100) Example 9 (1) -do .do do do do D0.

(100) Example 25 (1).. do Yellowish Yellow.. Brown Brown...- Considerable. (100) Example 26 (1).. .do d d do Do.

(100) Errample 27 (1).. Do.

butyl--mercaptobutyl-S-mercaptopropionate) (1).

EXAMPLE 28 Stabilizer test 1 1 wt. part of each of the thermal stabilizers Al-A4 and comparative A1-A4, listed in the following Table 1 was blended with 100 wt. parts of suspension-polymerized, commercially available polyvinyl chloride (p 800) and then the blended resin was kneaded thoroughly on a roll mixer kept at 150 C. for about 2 minutes and fabricated to a sheet, about 1 mm. thick. The resin sheet was introduced in a constant temperature chamber kept at EXAMPLE 29 Stabilizer test 2 wt. parts of a shock-proof resin prepared from 910 parts of suspension-polymerized, commercially available polyvinyl chloride (1 800) conditioned with 10 wt. parts of butadiene-styrene-methylmethacrylate copolymer (modifier) were added with 0.75 wt. part of the thermal stabilizer prepared in Example 3 or 5 and comparatively tested with similar samples conditioned with conventional compara-tive stabilizers. The results are listed in the following Table 2.

In this table, samples Bl-B2 which were conditioned with respective organo-tin compounds represented highly superior thermal stabilizing performance to those of conventional samples Comparative B1-B3. It was remarkably found that the samples B-l and B-2 conditioned with the stabilizer according to this invention, but prepared in highly different modes, showed substantially similar results.

TABLE 2 Degree of deceleration upon heated at 190 C. under pressure for several minutes: Nomination of samples Resin (parts) Stabilizer (parts) 5 10 15 B-l Polyvinyl chloride (90), butadienestyrene Example 3 (0.75).- Colorless Colorless Yeilowish.

methylmethacrylate copolymer B-2 .do Example 4 (0.75) do ..do Do. Comparative:

B-l .do Dibu7t5ltinbismaleate Yellowish- Yellow Brown. B-z do Exainpie 26 (0.75)-- do -d0 Yellow B-3 do Example 27 (0.75). do .do o

EXAMPLE 30 EXAMPLE 31 Results of several comparative tests on samples of polyvinyl chloride (p 800) conditioned with the :organotin compounds and conventional comparative non-toxic stabilizers are shown in the following Table 3. The tests were made in the similar way as mentioned hereinbefore in Example 28. In this table, acute toxicity values (LD50) of the organo-tin compounds are also shown.

The acute toxicity was measured upon culture of a certain number of rats for two weeks after oral dosing of each compound. Each test was made on 4 batches of rats, yeach batch consisting of 10 rats. The listed toxicity is the means value of 4-batch tests. With a dose of 10 g./kg. of each of the solid state organo-tin compound prepared by the process described in Examples 5, 6, 19, 20, 21, 22, 23 and 24, mortality was found nil, which means amazingly superior to those of conventional comparative non-toxic thermal stabilizers, and therefore the novel organo-tin compounds are highly suitable for use as conditioners for foodstul packaging synthetic film materials,

The 10W molecular distannoxane compound, comparative C-4 in the table, is better in its long period thermal A composition consisting of 100 wt. parts of suspensionpolymerized and commercially available polyvinyl chloride (p800) conditioned with the stabilizer, 1 wt. part, prepared in Example 6 or 8 and epoxidized soya bean oil, 2 parts, was extruded in its fused state from a blow extruder to provide a number of colorless and transparent bottles, and tests were made upon these hollow products for continuous workability, small-issuance and softening point (according to the Japanese Industrial Standards HSK-6745). The results are shown in a comparative way, in the following Table 4. In this table, sample: comparative D-1 contained a conventional tin-compound known as non-poisonous tin stabilizer.

Practically no smell was sensed from blown bottles with use of the novel stabilizers prepared in Examples 6 and 8, while in the case of sample D-l, considerable mercaptan smell was sensed. It was further found that with the solid state organic tin compounds according to the invention, the secondary transition temperature of the resin under test was subject to substantially no alteration. On the contrary, if conventional organic liquid tin-compounds were used in such quantities as to obtain similar stabilizing etlect as with use of the novel stabilizers, the secondary transition was considerably decreased.

TABLE 3 Resin, polyvinyl acute Degree of deooloration upon heated at 190 C.

chloride toxicity, under pressure for several minutes: Remarks: Nomination (p 800) LD mercaptan of samples (parts) Stabllzer (parts) (g./kg.) 10 15 20 smell Example 5(1) (1) Colorless.. Colorless Yellowish None, (100) Example 6 (l)- 0 d do D0. (100) Example 7 (1).. (100) Example 19 (1). (100) Example 20 (1)... (100) Example 21 (1)... (100) Example 22 (1)... (100) Example 23 (1)... (100) Example 24 (1) (100) di-n-octyl)t irbis(S,S'-diisooctyhnercapto- 2-4 Yellowish. Brown Blackish brownsmelled.

acetate 1 C2 (100) di-n-oetyl-tin-bismaleate polymer (1) 4. 6 Ycllowish. Yellowish brown .do aleate smell. C-3 (100) 1,1,3,3tetraoctyll,3-S,Sdibuty13-mer 1-2 Colorless.. Colorless Yellowish Smelled.

captopropionate-l,3-distannoxane (1). C-4 (100) 1,1,3,3tetraoctyl1,3-S,Sdioctyl8mercap 4.6 Coloress.. Colorless Yellowish Smelled.

topropionate-1,3distannoxane (1) 1 Over 10.

TABLE 4 softening Nomination Cont. Smell from temperature of sample Constituents of composition (parts) workabillty blown bottles (Tf C.

D-1 PV1 13((-r)i 800) (100); stabilizer o example 6 (1); epoxydized soya bean Better Odorless 74 o 2 D-2 PVC (p 800) (100); stabilizer of example 8 (1); epoxydized soya bean Yellowish .do 74 oil (2). decolored products. Comparative:

D-l PVC (p 800) (100); dinoctyletinbis(S, Sdiisooctyl-mercaptoace- .-..do Mercaptan 67 tate) (2); epoxydized soya bean oil (2). smell.

EXAMPLE 32 stability than the solid state organo-tin compounds according to this invention, but it is considerably inferior in its toxicity and ill smell than the inventive compounds.

polymerized and commercially available polyvinyl chlo- 19 ride (p 800) admixed with 15 Wt. parts of vinyl chloride (91)-cetyle vinyl ether (9) as copolymer component was blended with 1 wt. part of a novel and a conventional The reaction in this case (only referring towsample E-l) may be expressed as follows:

thermal stabilizer (refer to El-3 and comparative E-l 04H0 S-CHZCh-COO-CHz to 5 in the following Table 5), respectively, for com- 5 /Sn\ parson. o H s-CH on coo-CH This blended mass was then mixed carefully together 4 Z 2 2 on a roll mixer kept at 150 C. at about 2 minutes, and 04H9 transformed into a sheet, about 1 mm. thick. SD S*CHT CHZ COO CH2 In the progress of this mixmg and sheet-formlng proc- 04H0 C H ess, the novel compound was formed synthetically and Snzo 4 acted as the stabilizer. C H 04H The sheet was introduced into a constant temperature 4 SH S CH2 CHZ COO CH2 chamber kept at 180 C. for performlng a contlnuous and static workability test. CH

TABLE 5 Degree of decoloration upon heated at 180 C. under pressure for several minutes: Nomination o samples Resin Parts Stabilizer (parts) 0 15 30 45 60 E-l PVC (p800) (85) Product of Example 25 (0.65); Colorless... Colorless.. Colorless.. Colorless.. Yellowish Polyviuyl chloride (91)- (15) dibutyl-tin-oxide (0.35).

cetylvinyl ether (9)- copolymer. E-2 Same as above (85) Product of Example 26 (0.66); -..do do do do Do.

(16) dibutyl-tinpxide (0.34). E-3 do g5; Dibutyl-tin-oxide (1) .do do do do Do.

5 Comparative: i

E-l do (85) Product of Example 25 (1) do Yellowrsh. Yellow Brown Brown.

(15) E-2 do Product of Example 26(1) Co1or1ess .do .do .do Do.

E-3 do (85) Product of Example 27 (l) do do do do Do.

15 E-4 do 285g Dlbutyl-tin-bis (S,Sdibutyl3 ..-do .do do do Do.

(15) mereaptopropionate). (l). E-5 do ((85)) Dibutyl-tin-oxide (1) do YelloW... Brown Blackish.- Brown.

EXAMPLE 33 The results are listed in the following Table 5.

In this table, test results are also listed where conventional stabilizers prepared in Examples -27 were added with dialkyl tin oxide to provide corresponding novel solid state tin-compounds as stabilizers (refer to samples El-3).

Conditioned with these stabilizers, the samples were tested on continuous workability.

Comparing the results with those of samples comparative E-l to 6 the former showed superior stabilizing performance.

More specifically, the addition of dialkyl tin oxide to dimercapto-tin-compound in an equivalent quantity to the tin contained therein, will amazingly improve the desired performance.

The solid state high molecular tin compound mentioned in the foregoing Example 5 was tested on long period thermal stabilization effect. Test samples F-l, F-2, and F-3 shown in the following Table 6 were prepared for comparison in three Ways. Sample F-l was prepared in the regular synthetic process; F-2 was prepared from the starting materials: dioctyl tin oxide and pentaerithritol tetra 3mercaptopropionate were mixed together in a mortar at room temporature, while F-3 was prepared by blending them directly with polyvinyl chloride. The results are shown in the following Table 6. As seen from this table, it was surprisingly found that there was substantially no change in the long period thermal stabilizing eifect among these three differently prepared samples.

TABLE 6 Resin De v gree of decoloration upon heated Plliril' at 190 C. under pressure (5.800 for several minutes: (partsg Man condition of stabilizer (parts) 10 20 30 Example 5 (1) Colorless.. Yellowlsh. Yellow. (100) Mixing at room temperature Do. (100) Blend with resin (1) Do.

21 EXAMPLE 34 Each of solid state high molecular tin compounds G1- G9 and Comparative GlG4 mentioned in the following Table 7 was tested in the similar way as in the case of The small sheets stacks were tested in the similar way with varying pressing periods and possible decoloration was observed.

The results are listed in Table 8..

TABLE 7 iRshi D YV1I1 Y Degree of decoloration upon heated at 190 C. N i t under pressure for several minutes:

om na ion p of sample (parts) Stabilizer (parts) 10 15 20 g3g; xampe Ctlorless.. Colorless.. golprless.. gellowish.

xampe o o. e ow range.

xampe golorless.. gellowish.

xamp e e ow rown.

Example gmgm (Yvollrlrrlesmgellowish. xampe o. e ow ran e.

(100) Example 16(1 o .do Dag (100) Example 170)-..- de.. Yellowish do Brown.

(100) Example 18(1) do Colorless.. Colorless.. Yellowish.

Example go Yrllowish. Ye11ow Brlgwn. xamp e o o o.

(100) Example 27(1) d Do.

(100) Dibutyl-tinbis(S,S-octy do .do Do.

thioglycolate) Example 28. In the present case, howevr, the pressing 25 temperature was 190 C. in place of 180 C.

As will be clearly seen from Table 8, comparative samples H-1 and H-Z where two component materials TABLE 8 Resin Degree of deeoloration upon heated at 190 C. PVC under pressure for several minutes: Nomination (p 1000) of samples (parts) Stabilizer (parts) 5 15 25 (100) Di-nEoe(t/8t)inoxide (0.72); octyl-3mercaptopropio Colorless.. Colorless.. Yellowish.

ne e

(100) D-n-oetyI-tin-oxide (0.76); ethylene glycol-di(3mer .....do do Do.

captopropionate) (0.25).

(100) Di-n-octyl-tiu-oxide (0.74); trimethylol ethane-triC- .do .do Do.

mercaptopropionate) (0.26).

(100) Di-n-oetyl-tn-oxide (0.75); pentaerythritoltetra(3 do do Do.

captopropionate) (0.26).

(100) 1,1,3,3tetraocty11,3-S,S-octyl-3-mercaptopropionatedo do Do.

1,3distannoxa11e (l).

(100) Product of Ex. 7 (1) .do. Do.

(100) Product of Ex. 21 (l). Do.

(100) D1-noctyl-tmox1de(l) Brown Brown.. Blaekish Brown.

(100) Octyl3-mercaptoprop10nate (1) do Blaekish Brown. Do.

(100) Pentaerythritol-tetra(S-mercaptopropionate) (1) do do Do.

EXAMPLE Were blended separately which materials were same aS Novel organic tin compounds obtained in the foregoing Examples 5, 7, 2l and the like, and several conventional comparative thermal stabilizers were tested in the similar way as in the foregoing.

More specifically, an organic sulfur compound such as oxo-octyl-3-mercaptopropionate, ethylene glycol di-3- mercaptopropionate, trimethylol ethanetri 3 mercaptopropionate, pentaerythritol tetra 3 mercaptopropionate and dioctyl tin oxide in its equi-molar quantity to SH-radical of the organic sulfur compound were blended to a resin which was subjected to a kneading step in the course of which the desired organic tin-compound was synthetically formed and used for the thermal stabilization of the resin.

On the other hand, the same compound prepared in the regular process was blended in the similar way and used for the same stabilizing purpose.

The results of the both cases are shown in the following 65 Table 8.

In each of the former tests, the starting materials were blended with a certain quantity of polyvinyl chloride and processed on a roll kneader, kept at 150 C., for about 2 minutes, and transformed into a sheet, about 0.5 mm. thick, which was then cut into small pieces having certain dimensions such as 5 cm. x 5 cm.

4 pieces were inserted between a pair of chromiumplated pressure plates and then pressed on a testing press at 190 C. under 50 kgs/cm?.

wherein R1, R2, R3 and R4 are each an alkyl radical having 1 to l2 carbon atoms directly bonded to the tin atom; X and Y are each a mercapto-radical of a polyhydric mercapto-acid ester of a polyol having a sulfur atom directly bonded to tin; and Z is a member selected from the group consisting of oxygen and sulfur.

2. Organic tin compound as set forth in claim 1, wherein at least one of said alkyl radical is selected from the group consisting of butyl and n-octyl.

3. Organic tin compound as set forth in claim 1, wherein said polyol is a member selected from the group con- 23 a sisting of ethylene glycol, trimethylol ethane, pentaerythritol, mannitol and sorbitol.

4. Organic tin compound as set forth in claim 1, wherein said polyol is a partially esterized aliphatic acid Cl-Clg selected from the group consisting of pentaerythritol monoand distearate, pentaerythritol monoand dilaurate and pentaerythritol mono-and diacetate.

5. Organic tin compound as set forth in claim 1, wherein said mercapto-acid is thioglycolic acid.

6. Organic tin compound as set forth in claim 1, wherein said mercapto-acid is 3-mercaptopropionic acid.

7. Process for the manufacture of a dialkyl tin compound comprising reacting a mixture of a dialkyl tin oxide and a mercapto acid ester in a mol ratio of Sn/S of 1:1 in the presence of an inert solvent at elevated temperature for dehydration.

References Cited I UNITED STATES PATENTS 10/ 1957 Mack et al. 260-429.7X 1/ 1959 Leistner et al. 260-429-7X 2/ 1959 Leistner et al. 260-429.7

12/1962 Mack 260L4297 12/ 1966 Gloskey 2610-4297 8/ 1968 Hechenbleikner et a1. 260-429.7

12/ 1963 Mack 260-429.7

TOBIAS E. LEVOW, Primary Examiner W. F. W. BELLAMY, Assistant Examiner U.S. Cl. X.R. 

